Siri Sahib S. Khalsa, Alan Siu, Tiffani A. DeFreitas, Justin M. Cappuzzo, John S. Myseros, Suresh N. Magge, Chima O. Oluigbo and Robert F. Keating
Previous studies have indicated an association of Chiari malformation Type I (CM-I) and a small posterior fossa. Most of these studies have been limited by 2D quantitative methods, and more recent studies utilizing 3D methodologies are time-intensive with manual segmentation. The authors sought to develop a more automated tool to calculate the 3D posterior fossa volume, and correlate its changes after decompression with surgical outcomes.
A semiautomated segmentation program was developed, and used to compare the pre- and postoperative volumes of the posterior cranial fossa (PCF) and the CSF spaces (cisterna magna, prepontine cistern, and fourth ventricle) in a cohort of pediatric patients with CM-I. Volume changes were correlated with postoperative symptomatic improvements in headache, syrinx, tonsillar descent, cervicomedullary kinking, and overall surgical success.
Forty-two pediatric patients were included in this study. The mean percentage increase in PCF volume was significantly greater in patients who showed clinical improvement versus no improvement in headache (5.89% vs 1.54%, p < 0.05) and tonsillar descent (6.52% vs 2.57%, p < 0.05). Overall clinical success was associated with a larger postoperative PCF volume increase (p < 0.05). These clinical improvements were also significantly associated with a larger increase in the volume of the cisterna magna (p < 0.05). The increase in the caudal portion of the posterior fossa volume was also larger in patients who showed improvement in syrinx (6.63% vs 2.58%, p < 0.05) and cervicomedullary kinking (9.24% vs 3.79%, p < 0.05).
A greater increase in the postoperative PCF volume, and specifically an increase in the cisterna magna volume, was associated with a greater likelihood of clinical improvements in headache and tonsillar descent in patients with CM-I. Larger increases in the caudal portion of the posterior fossa volume were also associated with a greater likelihood of improvement in syrinx and cervicomedullary kinking.
Suresh N. Magge, Arthur R. Bartolozzi IV, Neil D. Almeida, Deki Tsering, John S. Myseros, Chima O. Oluigbo, Gary F. Rogers and Robert F. Keating
Sagittal craniosynostosis is managed with a wide variety of operative strategies. The current investigation compares the clinical outcomes of two widely performed techniques: pi craniectomy and minimally invasive endoscopic strip craniectomy (ESC) followed by helmet therapy.
This IRB-approved retrospective study examined patients diagnosed with nonsyndromic, single-suture sagittal craniosynostosis treated with either pi craniectomy or ESC. Included patients had a minimum postoperative follow-up of 5 months.
Fifty-one patients met the inclusion criteria (pi 21 patients, ESC 30 patients). Compared to patients who underwent ESC, the pi patients were older at the time of surgery (mean age 5.06 vs 3.11 months). The mean follow-up time was 23.2 months for ESC patients and 31.4 months for pi patients. Initial cranial index (CI) was similar between the groups, but postoperatively the ESC patients experienced a 12.3% mean increase in CI (from 0.685 to 0.767) compared to a 5.34% increase for the pi patients (from 0.684 to 0.719), and this difference was statistically significant (p < 0.001). Median hospital length of stay (1 vs 2 days) and operative duration (69.5 vs 93.3 minutes) were significantly less for ESC (p < 0.001 for both). The ESC patients showed a trend toward better results when surgery was done at younger ages. Craniectomy width in ESC cases was positively associated with CI improvement (slope of linear regression = 0.69, p = 0.026).
While both techniques effectively treated sagittal craniosynostosis, ESC showed superior results compared to pi craniectomy. ESC showed a trend for better outcomes when done at younger ages, although the trend did not reach statistical significance. A wider craniectomy width (up to 2 cm) was associated with better outcomes than smaller craniectomy widths among the ESC patients.
Matthew F. Sacino, Cheng-Ying Ho, Matthew T. Whitehead, Amy Kao, Dewi Depositario-Cabacar, John S. Myseros, Suresh N. Magge, Robert F. Keating, William D. Gaillard and Chima O. Oluigbo
Focal cortical dysplasia (FCD) is a common cause of medically intractable epilepsy that often may be treated by surgery. Following resection, many patients continue to experience seizures, necessitating a decision for further surgery to achieve the desired seizure outcomes. Few studies exist on the efficacy of reoperation for intractable epilepsy due to FCD in pediatric cohorts, including the definition of prognostic factors correlated with clinical benefit from further resection.
The authors retrospectively analyzed the medical records and MR images of 22 consecutive pediatric patients who underwent repeat FCD resection after unsuccessful first surgery at the Children's National Health System between March 2005 and April 2015.
Accounting for all reoperations, 13 (59%) of the 22 patients achieved complete seizure freedom and another 5 patients (23%) achieved significant improvement in seizure control. Univariate analysis demonstrated that concordance in electrocorticography (ECoG) and MRI localization (p = 0.005), and completeness of resection (p = 0.0001), were associated with seizure freedom after the first reoperation. Patients with discordant ECoG and MRI findings ultimately benefited from aggressive multilobe lobectomy or hemispherectomy. Repeat lesionectomies utilizing intraoperative MRI (iMRI; n = 9) achieved complete resection and seizure freedom in all cases.
Reoperation may be clinically beneficial in patients with intractable epilepsy due to FCD. Patients with concordant intraoperative ECoG and MRI localization may benefit from extended resection of residual dysplasia at the margins of the previous lesional cavity, and iMRI may offer benefits as a quality control mechanism to ensure that a complete resection has been accomplished. Patients with discordant findings may benefit from more aggressive resections at earlier stages to achieve better seizure control and ensure functional plasticity.
Chima O. Oluigbo, Jichuan Wang, Matthew T. Whitehead, Suresh Magge, John S. Myseros, Amanda Yaun, Dewi Depositario-Cabacar, William D. Gaillard and Robert Keating
Focal cortical dysplasia (FCD) is one of the most common causes of intractable epilepsy leading to surgery in children. The predictors of seizure freedom after surgical management for FCD are still unclear. The objective of this study was to perform a volumetric analysis of factors shown on the preresection and postresection brain MRI scans of patients who had undergone resective epilepsy surgery for cortical dysplasia and to determine the influence of these factors on seizure outcome.
The authors reviewed the medical records and brain images of 43 consecutive patients with focal MRI-documented abnormalities and a pathological diagnosis of FCD who had undergone surgical treatment for refractory epilepsy. Preoperative lesion volume and postoperative resection volume were calculated by manual segmentation using OsiriX PRO software.
Forty-three patients underwent first-time surgery for resection of an FCD. The age range of these patients at the time of surgery ranged from 2 months to 21.8 years (mean age 7.3 years). The median duration of follow-up was 20 months. The mean age at onset was 31.6 months (range 1 day to 168 months). Complete resection of the area of an FCD, as adjudged from the postoperative brain MR images, was significantly associated with seizure control (p = 0.0005). The odds of having good seizure control among those who underwent complete resection were about 6 times higher than those among the patients who did not undergo complete resection. Seizure control was not significantly associated with lesion volume (p = 0.46) or perilesion resection volume (p = 0.86).
The completeness of FCD resection in children is a significant predictor of seizure freedom. Neither lesion volume nor the further resection of perilesional tissue is predictive of seizure freedom.